1. Field
Exemplary embodiments of the invention relate to an illumination unit in which a light source is mounted on a transparent substrate and a vehicle lamp provided with the illumination unit.
2. Related Art
For example, JP 2013-214492 A describes a vehicle lamp having such a configuration that a light source is mounted on a transparent substrate.
In a vehicle lamp described in a third exemplary embodiment of JP 2013-214492 A, the transparent substrate is disposed in a lamp chamber defined by a transparent cover and a lamp body. An inner surface of the lamp body is configured to be a reflecting surface. With this configuration, light which is emitted from the light source to be directed rearwards is reflected by the reflecting surface of the lamp body to be directed forward. Furthermore, part of the reflected light is reflected by the transparent substrate to be directed rearward, so that the light is then reflected again to be directed forward by the reflecting surface of the lamp body.
In the vehicle lamp described in JP 2013-214492 A, the light emitted from the light source is reflected multiple times (multiple reflection) between the transparent substrate and the reflecting surface of the lamp body, thereby making it possible to improve the appearance of the lamp when the lamp is turned on.
In the vehicle lamp which utilizes the multiple reflection technique like this, however, a further improvement in the appearance of the vehicle lamp when the lamp is turned on is desired.
A further improvement in the appearance of a general illumination unit lamp when the lamp is turned on is also desired as well as the vehicle lamp.